Conventionally, technology described in Patent Documents 1 to 3, for example, is known as technology which irradiates each of a plurality of wells two-dimensionally arranged on the main surface of a microplate with measurement light (pumping light). With the technology described in Patent Document 1, the measurement light is irradiated from the back surface of the microplate to the well corresponding in parallel with the depth direction of the well. Solution of culture fluid, fluorescence indicator, evaluation compounds or the like, and the object to be measured such as cells are injected into each well arranged on the microplate.